Organic hydroxy silicates utilized as curing agents for polyurethane prepolymers

ABSTRACT

Liquid isocyanate-terminated polyurethane prepolymers are cured by mixing them with 10% to 200% by weight, based on the weight of the prepolymer, of an organic hydroxy silicate compound or their condensation product. The cured material may be non-porous elastomeric products or fine cellular products.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of my copending U.S. patentapplication, Ser. No. 663,924, filed Mar. 4, 1976, now U.S. Pat. No.4,097,424 which is a continuation-in-part of my earlier U.S. patentapplication, Ser. No. 599,000, filed July 7, 1975, now U.S. Pat. No.4,072,637 which is a continuation-in-part of my earlier U.S. patentapplication Ser. No. 262,485, filed June 14, 1972, now abandoned, whichis a continuation-in-part of my earlier U.S. patent application Ser. No.71,628, filed Sept. 11, 1970, now abandoned.

BACKGROUND OF THE INVENTION

This invention relates to a process for curing liquidisocyanate-terminated polyurethane prepolymers by mixing them with 10%to 200% by weight, based on the weight of the prepolymer, of an aqueousdispersion or solution of an organic hydroxy silicate compound and theircondensation products. This novel organic hydroxy silicate and theircondensation products are effective both as a curing agents and as a lowcost extender for polyurethane prepolymers. The products cured by thismethod may be quite varied in physical properties; they may be solid orporous, rigid or elastomeric, and the porous products may be rigid orsoft and flexible.

The products produced by curing liquid isocyanate-terminatedpolyurethane prepolymer may be utilized as thermal insulating material,noise insulating material, shock-resistant packaging, cushions, ascoating agents, as adehesives, as casting material, as constructionalcomponents of a building, etc.

The products have improved heat and flame resistant properties.

The organic hydroxy silicate compound and their condensation productsutilized in this process may be produced by the process of the Claimsand Examples in U.S. patent application Ser. No. 765,050, filed on Feb.2, 1977, by David H. Blount. Details of the process to produce siliconacids, hydrated silica and silicoformic acid, and the process to produceorganic hydroxy silicate compounds and their condensation products maybe found in that U.S. patent application. The Infrared KBr Analysis ofboth the silicon acids and organic hydroxy silicate compounds wereincluded in my U.S. patent application Ser. No. 765,050.

In U.S. patent application Ser. No. 663,924, filed on March 4, 1976, andU.S. patent application Ser. No. 599,000, filed on July 7, 1975, byDavid H. Blount, the silicon acids are reacted with polyisocyanatecompounds, but not with liquid isocyanate-terminated polyurethaneprepolymers. In U.S. Pat. Nos. 3,981,831; 3,975,316 and German Pat. No.2,325,090, an aqueous silica sol and silicates were utilized in theirprocess, but they did not utilize organic hydroxy silicate compounds andtheir condensation products to produce polyurethane products.

The silicon acids, hydrated silica and hydrated silica containing Si-Hbonds may be produced by any of the commonly known methods. They arepreferred to be in a fine granular form.

The silicon acids will react chemically with monohydroxy and polyhydroxyorganic compounds to produce organic hydroxy silicate compounds andtheir condensation products. These novel organic hydroxy silicatecompounds and condensation products will react chemically withisocyanates, organic acids, polycarboxylic acids and anhydrides andepoxy compounds.

The organic hydroxy silicate compounds and their condensation productsare produced by chemically reacting a silicon acid, such as hydratedsilica and hydrated silica containing Si-H groups with an organichydroxy compound, by heating the mixture in the presence of an alkalicatalyst to a temperature just below the boiling temperature of theorganic hydroxyl compound while agitating for 20 to 60 minutes atambient pressure, thereby producing organic hydroxy silicate compoundsand their condensation products.

Various alkali compounds such as alkali metal carbonates, hydroxides,oxides and alkali metal salts of weak acids may be used as the alkalicatalyst in the chemical reaction to produce organic hydroxy silicatecompounds and their condensation products. The preferred alkali compoundis sodium carbonate. Other useful alkali compounds are potassiumcarbonate, sodium hydroxide, potassium hydroxide and sodium silicate.Best results are obtained when the alkali catalyst is added in theamount of 1% to 10% of the weight of the reactants, hydrated silica andorganic hydroxyl compound. The alkali catalyst is necessary in thisprocess because when an organic hydroxyl compound is heated withhydrated silica without an alkali catalyst, no organic hydroxy silicatecompound is produced. It is possible to produce a colloidal dispersionof silica hydrogel in polyols when a silica hydrogel is heated in apolyol while agitating without the presence of an alkali catalyst, butnot an organic hydroxy silicate compound. Infrared analysis of acolloidal dispersion of silica hydrogen in polyols shows that the polyoldoes not react with the silica.

Various monohydroxy compounds may be used in this process to to produceorganic hydroxyl silicate compounds such as methyl, ethyl, propyl,isopropyl, butyl, isobutyl, amyl, hexyl, octyl, benzyl and allylalcohols and thioalcohols, phenols, cresols, thiophenols, cyclohexanol,methylcyclohexanol, cyclohexano-methanol, methallyl alcohol thiocresols,halogenated alcohols and mixtures thereof.

Various polyhydroxyl compounds may be used in this process to produceorganic hydroxyl silicate compounds and their condensation products suchas glycerol, glycerol monochlorohydrin, ethylene glycol, propyleneglycol, butylene glycol, trimethylene glycol, tetramethylene glycol,pentamethylene glycol, hexamethylene glycol, diethylene glycol,triethylene glycol, dipropylene glycol, tetraethylene glycol,polyethylene glycols, ether glycols, Bisphenol A, resorcinol bis(beta-hydroxyethyl) terephthalate,2-ethyl-2-(hydroxymethyl)-1,3-propanediol, pentaerythritol, trimetholpropane, trimethol ethane, 2,2-oxydiethanol, glucose, mannose, fructose,molasses, cane sugar, dextrines, starches, corn syrup, maple syrup,castor oil and mixtures thereof.

Various organic compounds containing hydroxyl radicals may be used toproduce organic hydroxy silicate compounds such as glycolic acid, malicacid, 10 hydroxy undecanoic acid, 2-hydroxy decanoic acid, 10 hydroxypentadecanoic acid, monoglycerides of fatty acids, halogenated alcohols,etc. and mixtures thereof.

One part by weight of an organic hydroxyl silicate compound and polymer,containing 0 to 1 part by weight of water may be reacted with 0.5 to 6parts by weight of a liquid isocyanate-terminated polyurethaneprepolymer to produce a solid/solid fine cellular polyurethane product.

Any suitable polyisocyanate may be used to produce the liquidisocyanate-terminated polyurethane prepolymer, for example, arylenepolyisocyanates such as tolylene, metaphenylene, 4-chlorophenylene-1,3-,methylene-bis-(phenylene-4-), biphenylene-4,4'-,3,3'-dimethoxy-biphenylene-4,4'-, 3,3'-diphenylbiphenylene-4,4'-,naphthalene-1,5- and tetrahydronaphthalene-1,5-diisocyanates andtriphenylmethane triisocyanate; alkylene polyisocyanates such asethylene, ethylidene, propylene-1,2-, butylene-1,4-, butylene-1,3-,hexylene-1,6-, decamethylene-1,10-, cyclohexylene-1,2-,cyclohexylene-1,4-, and methylene-bis-(cyclohexyl-4,4'-) diisocyanates.Phosgenation product of aniline-formaldehyde condensation may be used.Polyisothiocyanate, inorganic polyisothiocyanates, polyisocyanates whichcontain carbodiimide groups as described in German Pat. No. 1,092,007and polyisocyanates which contain urethane groups, allophanate groups,isocyanurate groups, urea groups, imide groups or biuret groups may beused to produce the liquid isocyanate-terminated polyurethaneprepolymers.

SUMMARY OF THE INVENTION

I have discovered that an aqueous solution or dispersion of organichydroxy silicate compounds and their condensation products will reactchemically with liquid isocyanate-terminated polyurethane prepolymers toproduce cured polyurethane products.

Water is mixed with the organic hydroxy silicate compounds and theircondensation products in the amount of 10% to 100% by weight, based onthe weight of the organic hydroxy silicate compound and theircondensation products. The pH of the mixture may be 6 to 12.

Any of the commonly known isocyanate-terminated liquid polyurethaneprepolymers may be reacted with and cured by the aqueous solution ordispersion of organic hydroxy silicate compounds and their condensationproducts.

As is known in the art, the isocyanate-terminated liquid polyurethaneprepolymers may be made by reacting organic polyisocyanates in molarexcess with hydroxyl containing or carboxyl-containing polyesters,polyethers, polysulfides, polybutadienes, butadiene-acrylonitrilecopolymer and butadiene-styrene copolymer, polyepichlorohydrin,polythioethers, polyester amides, polyacetals, urea formaldehyde resins,polycarbonates and other polyols. The polyesters may be produced by anyof the commonly known methods. The polyether polyols are useful inmaking polyurethane prepolymers, and the methods to produce them arewell known in the art. The hydroxyl-group-containing polysulfidepolymers maybe utilized to produce polyurethane prepolymers.

Any suitable polyisocyanate may be reacted with the above-describedhydroxyl-containing polymers to prepare the isocyanate-terminatedpolyurethane prepolymers such as the arylene polyisocyanates, alkylenepolyisocyanates and triphenylmethane triisocyanate as previously listedin this invention. Toluene diisocyanates are preferred, especially amixture of 80% of the 2,4-isomer and 20% of the 2,6-isomer thereof.

Plasticizers, fillers, curing rate modifiers, pigments, extender and thelike maybe added to the polyurethane prepolymer or may be added at thetime of curing and may be in the amount from 5% to 50% by weight, basedon the prepolymer. Plasticizers may include benzoate ester, phthalateesters, dipropylene glycol benzoate, dodecyl phthalate and propyleneglycol phthalate. Extenders such as high boiling coal tar distillates,mineral oil, poly (alpha-methyl styrene) polymers, mercapto-terminatedliquid polysulfide polymers, paraffin oil and sulphonated castor oil maybe used. Finely divided fillers such as alkali metal silicates, alkalineearth metal silicate, ammonium silicate, metal oxides, metal hydroxides,metal carbonates, chalk, heavy spar, gypsum, anhydrite, clay, kaolin,silica, and mixtures thereof may be used in this instant process.

In the production of certain foams, it is advisable to add blowingagents. These are inert liquids with boiling points ranging from -25° to80° C. and preferably from -15° to 40° . The organic blowing agents areused in quantities of from 2% to 30% by weight, based on the reactionmixture.

The organic blowing agents such as acetone, ethyl acetate, methanol,ethanol, halogenated alkanes, e.g. methylene chloride, chloroform,ethylidene chloride vinylidene chloride, monofluorotrichloromethane,chlorodifluoromethane, dichlorodifluoromethane, butane, hexane, heptane,diethylether, compounds which decompose at temperatures above roomtemperature with liberation of gases, e.g. nitrogen, such as azocompounds and azoisobutyric acid nitrile, may be used in this process.

Other catalysts in place of or combined with water may be utilized asthe catalyst to produce foam products from the liquidisocyanate-terminated polyurethane prepolymers and organic hydroxylsilicate compounds and their condensation product. These catalysts arecommonly known in the arts such as tertiary amines, silaamines, basiccompounds which contain nitrogen e.g. tetraalkylammonium hydroxides,alkali metal hydroxides, alkali phenolates, alkali metal alcolates,hexahydrotriazines, tin organo-metallic and mixtures thereof. Thesecatalysts are generally used in a quantity of from 0.001% to 10% byweight, based on the weight of the polyurethane prepolymer.

Suitable emulsifiers and foam stabilizers may also be used according tothis invention. Suitable emulsifiers are, e.g. the sodium salts ofricinoleic sulphonates or of fatty acids; or salts of fatty acids withamines, e.g. oleic acid diethylamine or stearic acid diethanolamine; oralkali metal or ammonium salts of sulphonic acids and fatty acids. Theseadditives are preferably used in quantities of from 0% to 20%, byweight, based on the reaction mixtures.

Suitable foam stabilizers are mainly water-soluble polyether siloxanesand those described in U.S. Pat. No. 3,629,308. These additives arepreferably used in quantities of from 0% to 20%, by weight, based on thereaction mixture.

Further examples of surface active additives, foam stabilizers, cellregulators, negative catalysts, stabilizers, flame retarding substances,plasticizers, dyes, fillers and fungicidal and bacteriocidal substancesand details about methods of using these additives and their actions maybe found in Kunststoff-Handbuch, Volume VI, published by Vieweg andHochtlen, Carl-Hanser-Verlag, Munich 1966, e.g. on page 103 to 113.

The polyurethane prepolymer with only two terminal isocyanate groupstend to produce non-porous products when reacted with an organic hydroxysilicate compound and polymer containing 10 to 100%, by weight of water.The polyurethane prepolymer with 3 or more terminal isocyanate groupstend to produce cellular products when reacted with an organic hydroxysilicate compound and polymer containing 10% to 100% by weight of water.The polyurethane prepolymer, when reacted with an organic hydroxysilicate compound and polymer without water added, tends to producenon-porous products. Mixtures of polyurethane prepolymer with three andfour terminal isocyanate groups and cured by reacting with an organichydroxy silicate compound and polymer containing 10% to 100% by weightproduce tough, strong, finely cellular, light weight polyurethaneproduct which is useful for structural applications. The three and fourterminal isocyanate groups may be mixed to contain from 20% to 80% byweight of the prepolymer having three isocyanate groups, and from 80% to20% by weight of the prepolymer having four isocyanate groups.

The object of the present invention is to provide a novel method ofcuring liquid isocyanate-terminated polyurethane prepolymers. Anotherobject and advantage of the present invention is to utilize low cost andready availability of organic hydroxy silicate compounds and theircondensation products to cure urethane prepolymers. Another object is toproduce relatively low cost elastomeric and foamed polyurethane polymershaving good physical properties. Another object of the present inventionis to produce polyurethane polymers with improved flame resistantproperties. Still a further object to provide novel relatively low cost,rigid, fine cellular, light-weight polyurethane polymers which may beused for structural purposes. Still another object is to produce novelpolyurethane polymers that are soluble in organic solvent and may beutilized as coating agents for wood and metal.

DESCRIPTION OF PREFERRED EMBODIMENT

My invention will be illustrated in greater detail by the specificexamples which follow, it being understood that these preferredembodiments are illustrative of, but not limited to, procedures whichmay be used in the production of polyurethane polymer utilizing organichydroxy silicates as the curing agent. Parts and percentages are byweight unless otherwise indicated.

EXAMPLE I

About equal parts by weight of fine granular hydrated silica andglycerol are mixed, then 5% by weight of sodium carbonate, percentagebased on the weight of the hydrated silica and glycerol, is added. Themixture is then heated to just below the boiling point of glycerol for20 to 30 minutes while agitating at ambient pressure, thereby producingbrown granules of glycerol silicate. On further heating of the glycerolsilicate at a temperature just below the boiling point of glycerol for10 to 30 minutes, the glycerol silicate granules soften, then form abrown poly(glycerol silicate) polymer.

The mixture of glycerol silicate and poly(glycerol silicate) polymerwere analyzed by Infrared KBr disc analysis and it showed evidence thatthe hydrated silica reacted chemically with the glycerol.

About 2 parts by weight of a liquid isocyanate-terminated polyurethaneprepolymer, which was produced by mixing about equal parts by weight oftoluene diisocyanate (80% 2,4-isomer and 20% 2,6-isomer) andpolyethylene glycol (380-420 mol wt.) and 1 part by weight of the saidmixture of glycerol silicate and poly(glycerol silicate) polymer,containing about 10% water by weight, are mixed. The mixture is gentlyagitated at ambient temperature for 5 to 15 minutes until the mixturebegins to expand. The mixture expands 8 to 10 times its original volumeand is cured within 30 to 60 minutes, thereby producing a white, rigid,tough polyurethane foam.

EXAMPLE II

About equal parts by weight of the mixture of glycerol silicate and poly(glycerol silicate) polymer as produced in Example I and water aremixed. Then equal parts by weight of the polyurethane prepolymerproduced in Example I are mixed. The mixture is then gently agitated for5 to 15 minutes until it begins to expand. The mixture expands 4 to 6times its original volume, thereby producing a tough semirigid foam in30 to 60 minutes.

EXAMPLE III

About 1 part by weight of the mixture of glycerol silicate and poly(glycerol silicate) polymer as produced in Example I and 0.5 part byweight of water are mixed, then equal parts by weight of thepolyurethane prepolymer as produced in Example I are mixed. The mixtureis gently agitated for 5 to 15 minutes until it begins to expand. Themixture expands 4 to 6 times its original volume, thereby producing atough, elastic, semirigid, foam and is cured in 30 to 60 minutes.

EXAMPLE IV

About equal parts by weight of castor oil and toluene diisocyanate (80%2,4-isomer and 20% 2,6-isomer) are mixed and agitated gently until thechemical reaction has stopped, thereby producing a polyurethaneprepolymer.

About 2 parts by weight of the polyurethane prepolymer as produced aboveand 1 part by weight of a catalyst, an aqueous solution of the mixtureof glycerol silicate and poly(glycerol silicate) polymer as produced inExample I containing 25% by weight of water, are mixed. The mixture isgently agitated for 5 to 15 minutes until it begins to expand. Themixture expands 6 to 8 times its original volume, thereby producing awhite, tough, semi-rigid polyurethane foam, a fine cellular product.

EXAMPLE V

About 1 part by weight of hydrated silica (SiO₂ ×H₂ O) and about 1.5parts by weight of propylene glycol and 1 to 10% sodium carbonate aremixed then heated to just below the boiling point of propylene glycol(150° to 180° C.) while agitating for 30 to 90 minutes at ambientpressure thereby producing brown granules of propylene glycol silicateand poly(propylene glycol silicate) polymer.

About 2 parts by weight of the polyurethane prepolymer as produced inExample I and 1 part by weight of the mixture of propylene glycolsilicate and poly(propylene glycol silicate) polymer, containing about10% water, are mixed then agitated gently for 5 to 15 minutes until themixture begins to expand. The mixture expands 8 to 12 times its originalvolume and is cured in 30 to 60 minutes, thereby producing a white,tough, rigid, polyurethane foam, a fine cellular product.

EXAMPLE VI

About 1 part of the mixture of propylene silicate and poly(propylenesilicate) polymer as produced in Example V and 0.5 parts by weight ofwater are mixed; then 1 part by weight of the mixture is mixed with 1.5parts by weight of the polyurethane prepolymer as produced in ExampleIV. The mixture is then gently agitated at ambient pressure for 5 to 15minutes until the mixture begins to expand. The mixture expands 6 to 8times its original volume, thereby producing a white, tough, semirigidfine cellular product.

EXAMPLE VII

About 1.5 parts by weight of 2,2'-oxydiethanol, 1 part by weight of finegranular hydrated silica and 0.2 parts by weight of sodium silicate aremixed then heated to just below the boiling temperature of2,2'-oxydiethanol while agitating for 20 to 90 minutes, therebyproducing a thick, light brown, liquid mixture of 2,2'-oxydiethanolsilicate and poly(2,2'-oxydiethanol silicate) polymer.

About equal parts by weight of unsaturated polyester resin, containingabout 20% styrene and toluene diisocyanate (80% 2,4-isomer and 20%2,6-isomer) were mixed at ambient temperature. About 2 parts of theabove mixture were mixed with 1 part by weight of the mixture of2,2'-oxydiethanol silicate and poly(2,2'-oxydiethanol silicate) polymer.The mixture was gently agitated at ambient pressure and temperature for5 to 15 minutes until the mixture began to expand. The mixture expands 4to 6 times its original volume, thereby producing a rigid, creamcolored, fine cellular polyurethane product.

EXAMPLE VIII

A polyester, having about 2,000 to 2,200 molecular weight and producedby condensation of a mixture of about 70% ethylene glycol and 30%propylene glycol with equimolar amount of adipic acid, was reacted withtolylene diisocyanate to produce a urethane prepolymer having an NOCcontent of about 3.5%.

About 4 parts by weight of the above polyurethane prepolymer was mixedwith 1 part by weight of an aqueous solution of the mixture of propylenesilicate and poly(propylene silicate) polymers containing 40% water,then the mixture was gently agitated for 5 to 15 minutes at ambienttemperature and pressure. The mixture is allowed to cure for 12 to 24hours, thereby producing a white, tough elastomer.

EXAMPLE IX

About 1 part by weight of a fine granular hydrated silica, 5 parts byweight of a 35% aqueous solution of 2-butyne-1,4-diol and 1 to 10%potassium carbonate are mixed then heated to 80 degree to 120 degree C.while agitating for 20 to 90 minutes, thereby producing a light, brownmixture of 2-butyne-1,4-diol silicate and poly(2-butyne-1,4-diolsilicate) polymer.

About 3 parts by weight of the polyurethane prepolymer as produced inExample VIII and 1 part by weight of an aqueous solution containing 70%by weight of the mixture of 2-butyne-1,4 diol silicate andpoly(2-butyne-1,4-diol silicate) polymer are mixed thoroughly and thencured at ambient temperature and pressure for 12 to 24 hours, therebyproducing a white tough elastomer.

EXAMPLE X

About 1 part by weight of fine granular hydrated silica, 3 parts byweight of triethylene glycol and 1% to 10% sodium carbonate are mixedthen heated to a temperature near the boiling point of triethyleneglycol (150 degrees to 250 degrees C.) while agitating at ambientpressure for 20 to 90 minutes, thereby producing a light brown, liquidmixture of triethylene glycol silicate and poly(triethylene glycolsilicate) polymer.

A polyester containing 4 mols of glycerol, 2.5 mols of adipic acid and0.5 mol of phthalic anhydride are mixed with tolylene diisocyanate inabout equal proportions to produce a polyurethane prepolymer.

About 2 parts by weight of said polyurethane prepolymer and 1 part byweight of a catalyst mixture of triethylene glycol silicate andpoly(triethylene glycol silicate) polymer, containing 20% water, 2% zincstearate, 0.05% dimethyl ethanol amine and 0.5% paraffin oil, are mixed.The mixture is then agitated gently for 5 to 15 minutes until themixture begins to expand. The mixture expands 8 to 10 times its originalvolume at ambient temperature and pressure, thereby producing a tough,rigid, fine cellular polyurethane product.

EXAMPLE XI

Polypropylene glycol having an average molecular weight of 450 to 500 isreacted with toluene diisocyanate in an NCO/OH molar ratio of about 2:1,thereby producing a liquid polyurethane prepolymer.

The said polyurethane prepolymer in the amount of 3 parts by weight weremixed with 3 parts by weight of poly(alpha-methyl styrene) polymer and 3parts by weight of the mixture of an aqueous solution of propylenesilicate and poly(prophylene silicate) polymer containing 20% water;then 1 part by weight of a liquid polysulfide polymer was added thenmixed thoroughly and the mixture cures in a short period of time,thereby producing a white elastomer.

EXAMPLE XII

A polyurethane prepolymer, produced by the reaction of a liquidhydroxyl-terminated polybutadiene with 2,4-tolylene diisocyanate andwhich has a free NCO content of about 4% and an aqueous solution oftriethylene glycol silicate and poly(triethylene glycol silicate)polymer as produced in Example X, containing 30% water, were mixedthoroughly and let stand for 12 to 24 hours, thereby producing anelastomer product. The product is further cured by heating at 70 degreesto 80 degrees C. for 3 to 4 hours. Mixed in the ratio of 3:1 by weight.

EXAMPLE XIII

A liquid polyester of the following composition: 16 moles of adipicacid, 16 moles of diethylene glycol, 1 mol of trimethylol propane, isreacted with toluene diisocyanate (80% 2,4-isomer and 2,6-isomer) in theratio of 2 to 1 to produce a liquid polyurethane prepolymer. Two partsby weight of the polyurethane prepolymer are mixed with 1 part by weightof a catalytic mixture, an aqueous solution of propylene glycol silicateand poly(propylene glycol silicate) polymer containing 25% water, 0.01%stannous octoate, 0.02% triethylenediamine, 5% sulphanated castor oil,2% ammonium oleate and 0.5% paraffin oil is added. The mixture is gentlyagitated for 5 to 15 minutes until the mixture begins to expand. Themixture expands 6 to 8 times its original volume, thereby producing aflexible foam. The product is further cured by heating at 70 degree to80 degree C. for 3 to 4 hours.

EXAMPLE XIV

About 1 part by weight of a fine granular hydrated silica, 2 parts byweight of castor oil and 1% by weight of sodium hydroxide flakes aremixed when heated to just below the boiling temperature of castor oilwhile agitating at ambient pressure for 20 to 90 minutes, therebyproducing a light brown castor oil silicate polymer.

About 1 part by weight of castor oil silicate polymer is mixed with 0.20parts by weight of water containing 10% sodium dioctyl suffosuccinateand 1% stannous octoate, and the mixture is then mixed with 2 parts byweight of a polyurethane prepolymer containing 2 parts by weight oftoluene diisocyanate (80% 2,4-isomer and 20% 2,6-isomer) and 1 part byweight of polyethylene glycol (450 to 500 molecular weight). The mixtureis gently agitated at ambient pressure and temperature for 5 to 15minutes until the mixture begins to expand. It is then poured into amold, and the mixture expands 8 to 10 times its original volume, therebyproducing a rigid, cream colored, polyurethane fine cellular product.

EXAMPLE XV

About 1 part by weight of the castor oil silicate polymer as produced inExample XIV and 1 part by weight of the polyurethane prepolymer asproduced in Example XIV are mixed thoroughly at ambient temperature andpressure. A solid, cream colored polyurethane is produced in 1 to 4hours.

EXAMPLE XVI

About 2 parts by weight of fine granular hydrated silica, 2 parts byweight of 2-ethyl-2(hydroxymethyl)-1,3-propanediol and 1% potassiumhydroxide are mixed. The mixture is heated to just below the boilingpoint of the mixture while agitating at ambient pressure for 20 to 90minutes, thereby producing tan granules of2-ethyl-2(hydroxymethyl)-1,3-propanediol silicate and polymer. About 1part by weight of said tan granules containing 30% water are added to 2parts by weight of the polyurethane prepolymer as produced in ExampleXIV then agitated gently until it begins to expand. The mixture expands8 to 10 times its original volume, thereby producing a cream colored,rigid, cellular product.

EXAMPLE XVII

About 1 part by weight of a fine granular hydrated silica, 2 parts byweight of granular cane sugar and 10% by weight of sodium carbonate aremixed. The mixture is heated to just above the melting temperature, butbelow the boiling temperature while agitating at ambient pressure for 20to 90 minutes, thereby producing brown granules of sugar silicatepolymer.

About 1 part by weight of the sugar silicate polymer and 1 part byweight of water are mixed then added to 4 parts by weight of thepolyurethane prepolymer as produced in Example XIV. The mixture isgently agitated for 5 to 15 minutes until the mixture begins to expand.The mixture expands 8 to 10 times its original volume, thereby producinga rigid polyurethane fine cellular product.

EXAMPLE XVIII

About 1 part by weight of a fine granular hydrated silica, 2 parts byweight of ethanol and 10% by weight, percentage based on weight of thereactants, of sodium carbonate are mixed then heated to just below theboiling temperatures of ethanol while agitating for 20 to 90 minutesthereby producing a fine granular mixture of ethyl silicate and diethylsilicate.

About 1 part by weight of the mixture of ethyl silicate and diethylsilicate are mixed with 1 part by weight of glacial acetic acid thenadded to 4 parts by weight of the polyurethane prepolymer as produced inExample XIV. The mixture is gently agitated for 5 to 15 minutes until itbegins to expand. The mixture expands 6 to 10 times its original volume,thereby producing a rigid, fine cellular polyurethane product.

EXAMPLE XIX

About 1 part by weight of a fine granular hydrated silica, 2 parts byweight of propanol and 5% by weight of potassium carbonate are mixedthen heated to just below the boiling temperature of propanol whileagitating at ambient pressure for 20 to 90 minutes, thereby producing amixture of propanol silicate and dipropanol silicate.

About 1 part by weight of the mixture of propanol silicate anddipropanol silicate is mixed with 0.5 parts by weight of water thenmixed with 2 parts by weight of the polyurethane prepolymer as producedin Example IV. The mixture is gently agitated for 5 to 15 minutes atambient pressure and temperature until the mixture begins to expand. Themixture expands 6 to 10 times its original volume, thereby producing atough fine, cellular semi-rigid product.

EXAMPLE XX

About 1 part by weight of a fine granular hydrated silica, 2 parts byweight of butanol and 10% by weight of sodium carbonate are mixed thenheated in a closed system to just below the boiling temperature of thebutanol while agitating at ambient pressure for 20 to 90 minutes,thereby producing a white, granular mixture of butanol silicate anddibutanol silicate.

About 1 part by weight of the mixture of butanol silicate and dibutanolsilicate with 0.25 parts by weight of water are mixed with 1 part byweight of the polyurethane prepolymer as produced in Example I and 1part by weight of the polyurethane prepolymer as produced in ExampleXIV. The mixture is gently agitated for 5 to 15 minutes until it beginsto expand. It expands to about 8 to 12 times its original volume,thereby producing a rigid, fine cellular polyurethane product.

EXAMPLE XXI

About 1 part by weight of a fine granular hydrated silica, 2 parts byweight of isopropyl alcohol (70% alcohol with 30% water) and 10% byweight of sodium carbonate are mixed then heated in a closed system tojust below the boiling temperature of the isopropyl alcohol whileagitating at ambient pressure for 20 to 90 minutes, thereby producing awhite granular mixture of isopropyl alcohol silicate and diisopropylalcohol silicate.

About 1 part by weight of the mixture of isopropyl alcohol silicate anddiisopropyl alcohol silicate containing about 20% by weight of water aremixed with 3 parts by weight of the polyurethane prepolymer as producedin Example I. The mixture is gently agitated for 5 to 15 minutes untilit begins to expand. It expands 8 to 12 times its original volume,thereby producing a rigid, fine cellular polyurethane product.

The amount of polyurethane is reduced to only 0.5 parts by weight andthen mixed in the same manner, thereby producing a solid, whitepolyurethane product.

EXAMPLE XXII

About 1 part by weight of fine granular hydrated silica, 3 parts byweight of caprylic alcohol and 10% by weight (percentage based on theweight of hydrated silica and caprylic alcohol of sodium carbonate aremixed then heated to just below the boiling temperature of caprylicalcohol while agitating at ambient pressure for 20 to 90 minutes,thereby producing a mixture of caprylic alcohol silicate and dicaprylicalcohol silicate.

About 1 part by weight of the mixture of caprylic alcohol silicate anddicaprylic silicate is mixed with 1 part by weight of water, containing10% sodium dioctyl sulfosuccinate. The mixture is mixed with thepolyurethane prepolymer as produced in Example XIII in the ratio of 1 to2 parts by weight, then 0.5 part by weight of resinous extender, coaltar, is added. The mixture is gently agitated for 5 to 15 minutes atambient pressure and temperature until the mixture begins to expand. Themixture expands 8 to 12 times its original volume thereby producing asemi-flexible fine cellular product.

Other monohydroxy compounds may be used in place of caprylic alcoholsuch as methyl alcohol, ethyl alcohol, propyl alcohol, isobutyl alcohol,amyl alcohol, hexyl alcohol, octyl alcohol, allyl alcohols,thioalcohols, phenols, cyclohexanol, methylcyclohexanol, benzyl alcohol,cyclohexanomethanol, methallylalcohol, cresols, thiophenols,thiocresols, halogenated alcohols and mixtures thereof.

EXAMPLE XXIII

About 1 part by weight of fine granular hydrated silica, 2 parts byweight of glycolic acid and 10% by weight of sodium carbonate are mixedthen heated to just below the boiling temperature of glycolic acid whileagitating at ambient pressure for 20 to 90 minutes, thereby producing agray, granular mixture of glycolic acid silicate and poly (glycolic acidsilicate) polymer.

One part by weight of the mixture of glycolic acid silicate and poly(glycolic acid silicate) polymer are mixed with 1 part by weight ofwater containing 10% sodium dioctyl sulfosuccinate and 3% soap. One partby weight of the catalytic mixture is added to 1 part by weight of thepolyurethane prepolymer as produced in Example I and 1 part by weight ofthe polyurethane prepolymer as produced in Example XIII then gentlyagitating at ambient temperature and pressure for 5 to 10 minutes untilthe mixture begins to expand. The mixture expands 4 to 6 times itsoriginal volume, thereby producing a semiflexible, white in color,tough, polyurethane fine cellular product.

EXAMPLE XXIV

About 2 parts by weight of malic acid, 1 part by weight of fine granularhydrated silica and 5% by weight of potassium hydroxide are mixed thenheated to just below the boiling temperature of malic acid whileagitating at ambient pressure for 20 to 90 minutes, thereby producing agranular mixture of malic acid silicate and poly (malic acid silicate)polymer.

The mixture of malic acid silicate and poly (malic acid silicate)polymer is mixed with water in the ratio of 4 to 1 parts by weight thenadded to a polyurethane prepolymer, produced by reacting a trifunctionalpolypropylene glycol, having an average molecular weight of about 400,with tolylene diisocyanate to obtain a prepolymer having about 3% NCOgroups, in the ratio of 1 to 2 parts by weight, then gently agitated atambient pressure and temperature for 5 to 15 minutes until the mixturebegins to expand, thereby producing a rigid, finely cellular,polyurethane product in 30 to 120 minutes.

Other suitable organic compounds containing hydroxyl and carboxylicradical may be used in place of malic acid such as 10 hydroxy undecanoicacid, 2-hydroxy decanoic acid, 10 hydroxy pentadecanoic acid,monoglycerides of hard fatty acids and mixtures thereof.

EXAMPLE XXV

One part by weight of a fine silica hydrate, 2 parts by weight of2-chloroethanol and 10% by weight of sodium carbonate and mixed thenheated to just below the boiling point of 2-chloroethanol whileagitating at ambient pressure for 20 to 90 minutes, thereby producing awhite, granular mixture of 2-chloroethanol silicate anddi(2-chloroethanol) silicate.

About 1 part by weight of the mixture of 2-chloroethanol silicate anddi(2-chloroethanol) silicate, containing 25% water, and 2 parts byweight of a polyurethane prepolymer, prepared by reacting 3 parts byweight of polypropylene glycol (mol weight of 400 to 450) with 2 partsby weight of toluene diisocyanate (HYLENE TM), are mixed then gentlyagitated for 5 to 15 minutes until the mixture begins to expand, therebyproducing a semi-rigid, fine cellular, cured polyurethane product.

EXAMPLE XXVI

One part by weight of the mixture of glycerol silicate and poly(glycerol silicate) polymer as produced in Example I, 2 parts by weightof the mixture of isopropyl silicate and diisopropyl silicate asproduced in Example XXI and 1 part by weight of water are mixed.

One part by weight of the said mixture is added to 1.5 parts by weightof a liquid isocyanate terminated polyurethane prepolymer, produced byreacting a polyester resin, containing 4 parts by weight of ethyleneglycol, 1 part by weight of propylene glycol and an equimolar amount ofadipic acid and has a molecular weight of about 1800, with methylenebis-phenyl diisocyanate. About 0.5 part by weight of dipropylene glycoldibenzoate is added. The mixture is gently agitated for 5 to 15 minutes.The mixture cures after 4 to 12 hours to a solid, non-porous product.

EXAMPLE XXVII

About 1 part by weight of a fine, granular hydrated silica, 2 parts byweight of phenol and 1% to 10% sodium carbonate were mixed then heatedto just below the boiling temperature of the phenol while agitating atambient pressure for 20 to 90 minutes, thereby producing granules ofphenol silicate.

About 1 part by weight of phenol silicate is mixed with 10% to 100% byweight of water, based on the weight of phenol silicate and then mixedwith 2 parts by weight of a liquid isocyanate-terminated polyurethaneprepolymer, which is produced by reacting toluene diisocyanate (80%,2,4-isomer and 20% 2,6-isomer) with a trifunctional polypropylene(average mol wt. about 4000) to obtain a trifunctional prepolymer having2.7% NCO groups. The mixture is gently agitated for 5 to 15 minutesuntil it begins to expand. The mixture expands 8 to 12 times itsoriginal volume, thereby producing a tough, rigid, fine cellularpolyurethane product.

EXAMPLE XXVIII

About 1 part by weight of the phenol silicate as produced in ExampleXXVII and 0.25 parts by weight of water are mixed. The mixture is mixedwith 2 parts by weight of a mixture of liquid isocyanate-terminatedpolyurethane prepolymer, containing 80% to 20% by weight of theprepolymer having three isocyanate groups as produced in Example XXIVIIand 20% to 80% by weight of the prepolymer having four isocyanate groupsper molecule which is produced by reacting toluene diisocyanate (80%2,4-isomer and 20% 2,6-isomer) with a tetrafunctional polypropyleneglycol (average mol. wt. of about 450 to 500) to obtain a polyurethaneprepolymer having about 25% NCO groups. The mixture is gently agitatedfor 5 to 15 minutes until it begins to expand. The mixture expands 6 to12 times its original volume, thereby producing a tough, rigid, finecellular polyurethane product.

Although specific materials and conditions were set forth in the aboveExamples, these were merely illustrative of preferred embodiments of myinvention. Various other compositions, such as the typical materialslisted above may be used, where suitable. The reactive mixtures andproducts of my invention may have other agents added thereto to enhanceor otherwise modify the reaction and products.

Other modifications of my invention will occur to those skilled in theart upon reading my disclosure. These are intended to be included withinthe scope of my invention, as defined in the appended claims.

I claim:
 1. The process for curing a liquid isocyanate-terminatedpolyurethane prepolymer with a mixture of an organic hydroxy silicatecompound and polymer to produce a polyurethane product by the followingsteps:(a) adding 1 part by weight of a mixture of an organic hydroxysilicate compound and polymer, produced by heating about 1 part byweight of a fine granular hydrated silica with 1 to 3 parts by weight ofan organic hydroxy compound in the presence of an alkali catalyst whileagitating for 20 to 90 minutes, to up to 1 part by weight of water; (b)admixing 0.5 to 6 parts by weight of a liquid isocyanate-terminatedpolyurethane prepolymer to the said mixture; (c) agitating said mixturefor 5 to 15 minutes, thereby (d) producing a polyurethane product. 2.The process of claim 1 wherein the organic hydroxy compound is selectedfrom the group consisting of methyl alcohol, ethyl alcohol, propylalcohol, isopropyl alcohol, butyl alcohol, isobutyl alcohol, amylalcohol, hexyl alcohol, octyl alcohol, allyl alcohol, caprylic alcohol,thioalcohols, phenol, cresols, thiophenols, cyclohexanol,methylcyclohexanol, benzyl alcohol, cyclohexano-methanol, methallylalcohol, thiocresols, halogenated alcohols, glycerol, glycerolmonochlorohydrin, ethylene glycol, propylene glycol, butylene glycol,trimethylene glycol, tetramethylene glycol, pentamethylene glycol,hexamethylene glycol, diethylene glycol, triethylene glycol, dipropyleneglycol, tetraethylene glycol, polyethylene glycol, polypropylene glycol,ether glycols, Bisphenol A, resorcinol, bis(beta-hydroxy-ethyl)terephthalate, 2-ethyl-2-(hydroxymethyl)-1,3-propanediol,pentaerythritol, trimethylol propane, trimethylol ethane,2,2-oxydiethanol, glucose, mannose, fructose, molasses, cane sugar,dextrines, starches, corn syrup, maple syrup, castor oil, glycolic acid,malic acid, 10 hydroxy undecanoic acid, 2-hydroxy decanoic acid,10-hydroxy pentadecanoic acid, monoglycerides of hard fatty acids andmixures thereof.
 3. The process of claim 1 wherein 1% to 10% by weightbased on the weight of the organic hydroxy compound, of the alkalicatalyst is used, and the alkali catalyst is selected from the groupconsisting of sodium carbonate, potassium carbonate, sodium hydroxide,potassium hydroxide and mixtures thereof.
 4. The process of claim 1wherein said liquid isocyanate-terminated polyurethane prepolymer isselected from the group consisting of isocyanate-terminated polyester,isocyanate-terminated polyether, isocyanate-terminated polybutadiene,isocyanate-terminated polysulfide and mixtures thereof.
 5. The processof claim 1 wherein from 10% to 50% by weight, based on the weight ofpolyurethane prepolymer of a resinous extender, selected from the groupof resinous extenders consisting of alpha-methylstyrene, mineral oil,coal tar, paraffin oil, sulphonated castor oil, mercapto-terminatedliquid polysulfide polymers and mixtures thereof, is added to thepolyurethane prepolymer.
 6. The process of claim 1 wherein the liquidisocyanate-terminated polyurethane prepolymer is a mixture of at leastone liquid polyurethane prepolymer having three free isocyanate groupsand at least one liquid polyurethane prepolymer having four freeisocyanate groups; reacting said mixture with from 10% to 100% byweight, based on the weight of said mixture, of an organic hydroxysilicate compound and polymer containing 10% to 100% by weight of water,based on the weight of organic hydroxy silicate compound and polymer, bythoroughly mixing for 5 to 15 minutes until the mixture begins toexpand, thereby producing a rigid, fine cellular polyurethane product.7. The process of claim 6 wherein the mixture of polyurethaneprepolymers contains from 20% to 80% by weight of the prepolymer havingthree isocyanate groups and from 80% to 20% by weight of the prepolymerhaving four isocyanate groups.
 8. The process of claim 1 wherein 5% to50% by weight, based on the weight of the polyurethane prepolymer, of aplasticizer, selected from a group of aromatic esters consisting of abenzoate ester, a phthalate ester, a polyester benzoate or mixturethereof, is added to the polyurethane prepolymer.
 9. The process ofclaim 1 wherein the liquid isocyanate-terminated polyurethane prepolymeris a liquid polyurethane prepolymer having at least three freeisocyanate groups per molecule and a molecular weight of 400 to 5000 andis thoroughly mixed with from 10% to 100% by weight, based on weight ofpolyurethane prepolymer, of a mixture of organic hydroxy silicatecompound and polymer containing 10% to 100% by weight of water, based onthe weight of organic silicate compound and polymer, then gentlyagitated for 5 to 15 minutes until the mixture begins to expand, therebyproducing a rigid, fine cellular polyurethane product.
 10. The processof claim 1 wherein the organic hydroxy compound is an organicpolyhydroxy compound.
 11. The process of claim 1 wherein the organichydroxy compound is an organic monohydroxy compound.
 12. The product ofthe process of claim 1 wherein said liquid prepolymer is anisocyanate-terminated polyester.
 13. The product of the process of claim1 wherein said liquid prepolymer is an isocyanate-terminated polyether.14. The product of the process of claim 1 wherein said liquid prepolymeris an isocyanate-terminated polybutadiene.
 15. The product of theprocess of claim 1 wherein said liquid prepolymer is anisocyanate-terminated polysulfide.
 16. The product of the process ofclaim
 1. 17. The process of claim 1, wherein the mixture in step (b) ofclaim 1 contains from 0.001% to 10% by weight, based on the reactionmixture, of a catalyst selected from the group consisting of tertiaryamines, silaamines, tetraalkylammonium hydroxides, alkali metalhydroxides, alkali metal phenolates, alkali metal alcolates,hexahydrotriazines, tin organo-metallic compounds and mixtures thereof.18. The process of claim 1, wherein the mixture in step (b) of claim 1contains up to 20% by weight, based on the reaction mixture of a foamstabilizer.
 19. The process of claim 1, wherein the mixture in step (b)of claim 1 contains up to 20% by weight, based on the reaction mixtureof an emulsifying agent.
 20. The process of claim 1, wherein thereaction is accompanied by foaming.
 21. The process of claim 1, whereinthe mixture contains 5% to 50% by weight, based on the weight of thepolyurethane prepolymer, of a filler.